1// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
2/******************************************************************************
3 *
4 * Module Name: hwxface - Public ACPICA hardware interfaces
5 *
6 * Copyright (C) 2000 - 2025, Intel Corp.
7 *
8 *****************************************************************************/
9
10#define EXPORT_ACPI_INTERFACES
11
12#include <acpi/acpi.h>
13#include "accommon.h"
14#include "acnamesp.h"
15
16#define _COMPONENT ACPI_HARDWARE
17ACPI_MODULE_NAME("hwxface")
18
19/******************************************************************************
20 *
21 * FUNCTION: acpi_reset
22 *
23 * PARAMETERS: None
24 *
25 * RETURN: Status
26 *
27 * DESCRIPTION: Set reset register in memory or IO space. Note: Does not
28 * support reset register in PCI config space, this must be
29 * handled separately.
30 *
31 ******************************************************************************/
32acpi_status acpi_reset(void)
33{
34 struct acpi_generic_address *reset_reg;
35 acpi_status status;
36
37 ACPI_FUNCTION_TRACE(acpi_reset);
38
39 reset_reg = &acpi_gbl_FADT.reset_register;
40
41 /* Check if the reset register is supported */
42
43 if (!(acpi_gbl_FADT.flags & ACPI_FADT_RESET_REGISTER) ||
44 !reset_reg->address) {
45 return_ACPI_STATUS(AE_NOT_EXIST);
46 }
47
48 if (reset_reg->space_id == ACPI_ADR_SPACE_SYSTEM_IO) {
49 /*
50 * For I/O space, write directly to the OSL. This bypasses the port
51 * validation mechanism, which may block a valid write to the reset
52 * register.
53 *
54 * NOTE:
55 * The ACPI spec requires the reset register width to be 8, so we
56 * hardcode it here and ignore the FADT value. This maintains
57 * compatibility with other ACPI implementations that have allowed
58 * BIOS code with bad register width values to go unnoticed.
59 */
60 status = acpi_os_write_port(address: (acpi_io_address)reset_reg->address,
61 value: acpi_gbl_FADT.reset_value,
62 ACPI_RESET_REGISTER_WIDTH);
63 } else {
64 /* Write the reset value to the reset register */
65
66 status = acpi_hw_write(value: acpi_gbl_FADT.reset_value, reg: reset_reg);
67 }
68
69 return_ACPI_STATUS(status);
70}
71
72ACPI_EXPORT_SYMBOL(acpi_reset)
73
74/******************************************************************************
75 *
76 * FUNCTION: acpi_read
77 *
78 * PARAMETERS: value - Where the value is returned
79 * reg - GAS register structure
80 *
81 * RETURN: Status
82 *
83 * DESCRIPTION: Read from either memory or IO space.
84 *
85 * LIMITATIONS: <These limitations also apply to acpi_write>
86 * bit_width must be exactly 8, 16, 32, or 64.
87 * space_ID must be system_memory or system_IO.
88 * bit_offset and access_width are currently ignored, as there has
89 * not been a need to implement these.
90 *
91 ******************************************************************************/
92acpi_status acpi_read(u64 *return_value, struct acpi_generic_address *reg)
93{
94 acpi_status status;
95
96 ACPI_FUNCTION_NAME(acpi_read);
97
98 status = acpi_hw_read(value: return_value, reg);
99 return (status);
100}
101
102ACPI_EXPORT_SYMBOL(acpi_read)
103
104/******************************************************************************
105 *
106 * FUNCTION: acpi_write
107 *
108 * PARAMETERS: value - Value to be written
109 * reg - GAS register structure
110 *
111 * RETURN: Status
112 *
113 * DESCRIPTION: Write to either memory or IO space.
114 *
115 ******************************************************************************/
116acpi_status acpi_write(u64 value, struct acpi_generic_address *reg)
117{
118 acpi_status status;
119
120 ACPI_FUNCTION_NAME(acpi_write);
121
122 status = acpi_hw_write(value, reg);
123 return (status);
124}
125
126ACPI_EXPORT_SYMBOL(acpi_write)
127
128#if (!ACPI_REDUCED_HARDWARE)
129/*******************************************************************************
130 *
131 * FUNCTION: acpi_read_bit_register
132 *
133 * PARAMETERS: register_id - ID of ACPI Bit Register to access
134 * return_value - Value that was read from the register,
135 * normalized to bit position zero.
136 *
137 * RETURN: Status and the value read from the specified Register. Value
138 * returned is normalized to bit0 (is shifted all the way right)
139 *
140 * DESCRIPTION: ACPI bit_register read function. Does not acquire the HW lock.
141 *
142 * SUPPORTS: Bit fields in PM1 Status, PM1 Enable, PM1 Control, and
143 * PM2 Control.
144 *
145 * Note: The hardware lock is not required when reading the ACPI bit registers
146 * since almost all of them are single bit and it does not matter that
147 * the parent hardware register can be split across two physical
148 * registers. The only multi-bit field is SLP_TYP in the PM1 control
149 * register, but this field does not cross an 8-bit boundary (nor does
150 * it make much sense to actually read this field.)
151 *
152 ******************************************************************************/
153acpi_status acpi_read_bit_register(u32 register_id, u32 *return_value)
154{
155 struct acpi_bit_register_info *bit_reg_info;
156 u32 register_value;
157 u32 value;
158 acpi_status status;
159
160 ACPI_FUNCTION_TRACE_U32(acpi_read_bit_register, register_id);
161
162 /* Get the info structure corresponding to the requested ACPI Register */
163
164 bit_reg_info = acpi_hw_get_bit_register_info(register_id);
165 if (!bit_reg_info) {
166 return_ACPI_STATUS(AE_BAD_PARAMETER);
167 }
168
169 /* Read the entire parent register */
170
171 status = acpi_hw_register_read(register_id: bit_reg_info->parent_register,
172 return_value: &register_value);
173 if (ACPI_FAILURE(status)) {
174 return_ACPI_STATUS(status);
175 }
176
177 /* Normalize the value that was read, mask off other bits */
178
179 value = ((register_value & bit_reg_info->access_bit_mask)
180 >> bit_reg_info->bit_position);
181
182 ACPI_DEBUG_PRINT((ACPI_DB_IO,
183 "BitReg %X, ParentReg %X, Actual %8.8X, ReturnValue %8.8X\n",
184 register_id, bit_reg_info->parent_register,
185 register_value, value));
186
187 *return_value = value;
188 return_ACPI_STATUS(AE_OK);
189}
190
191ACPI_EXPORT_SYMBOL(acpi_read_bit_register)
192
193/*******************************************************************************
194 *
195 * FUNCTION: acpi_write_bit_register
196 *
197 * PARAMETERS: register_id - ID of ACPI Bit Register to access
198 * value - Value to write to the register, in bit
199 * position zero. The bit is automatically
200 * shifted to the correct position.
201 *
202 * RETURN: Status
203 *
204 * DESCRIPTION: ACPI Bit Register write function. Acquires the hardware lock
205 * since most operations require a read/modify/write sequence.
206 *
207 * SUPPORTS: Bit fields in PM1 Status, PM1 Enable, PM1 Control, and
208 * PM2 Control.
209 *
210 * Note that at this level, the fact that there may be actually two
211 * hardware registers (A and B - and B may not exist) is abstracted.
212 *
213 ******************************************************************************/
214acpi_status acpi_write_bit_register(u32 register_id, u32 value)
215{
216 struct acpi_bit_register_info *bit_reg_info;
217 acpi_cpu_flags lock_flags;
218 u32 register_value;
219 acpi_status status = AE_OK;
220
221 ACPI_FUNCTION_TRACE_U32(acpi_write_bit_register, register_id);
222
223 /* Get the info structure corresponding to the requested ACPI Register */
224
225 bit_reg_info = acpi_hw_get_bit_register_info(register_id);
226 if (!bit_reg_info) {
227 return_ACPI_STATUS(AE_BAD_PARAMETER);
228 }
229
230 lock_flags = acpi_os_acquire_raw_lock(lockp: acpi_gbl_hardware_lock);
231
232 /*
233 * At this point, we know that the parent register is one of the
234 * following: PM1 Status, PM1 Enable, PM1 Control, or PM2 Control
235 */
236 if (bit_reg_info->parent_register != ACPI_REGISTER_PM1_STATUS) {
237 /*
238 * 1) Case for PM1 Enable, PM1 Control, and PM2 Control
239 *
240 * Perform a register read to preserve the bits that we are not
241 * interested in
242 */
243 status = acpi_hw_register_read(register_id: bit_reg_info->parent_register,
244 return_value: &register_value);
245 if (ACPI_FAILURE(status)) {
246 goto unlock_and_exit;
247 }
248
249 /*
250 * Insert the input bit into the value that was just read
251 * and write the register
252 */
253 ACPI_REGISTER_INSERT_VALUE(register_value,
254 bit_reg_info->bit_position,
255 bit_reg_info->access_bit_mask,
256 value);
257
258 status = acpi_hw_register_write(register_id: bit_reg_info->parent_register,
259 value: register_value);
260 } else {
261 /*
262 * 2) Case for PM1 Status
263 *
264 * The Status register is different from the rest. Clear an event
265 * by writing 1, writing 0 has no effect. So, the only relevant
266 * information is the single bit we're interested in, all others
267 * should be written as 0 so they will be left unchanged.
268 */
269 register_value = ACPI_REGISTER_PREPARE_BITS(value,
270 bit_reg_info->
271 bit_position,
272 bit_reg_info->
273 access_bit_mask);
274
275 /* No need to write the register if value is all zeros */
276
277 if (register_value) {
278 status =
279 acpi_hw_register_write(ACPI_REGISTER_PM1_STATUS,
280 value: register_value);
281 }
282 }
283
284 ACPI_DEBUG_PRINT((ACPI_DB_IO,
285 "BitReg %X, ParentReg %X, Value %8.8X, Actual %8.8X\n",
286 register_id, bit_reg_info->parent_register, value,
287 register_value));
288
289unlock_and_exit:
290
291 acpi_os_release_raw_lock(lockp: acpi_gbl_hardware_lock, flags: lock_flags);
292 return_ACPI_STATUS(status);
293}
294
295ACPI_EXPORT_SYMBOL(acpi_write_bit_register)
296#endif /* !ACPI_REDUCED_HARDWARE */
297/*******************************************************************************
298 *
299 * FUNCTION: acpi_get_sleep_type_data
300 *
301 * PARAMETERS: sleep_state - Numeric sleep state
302 * *sleep_type_a - Where SLP_TYPa is returned
303 * *sleep_type_b - Where SLP_TYPb is returned
304 *
305 * RETURN: Status
306 *
307 * DESCRIPTION: Obtain the SLP_TYPa and SLP_TYPb values for the requested
308 * sleep state via the appropriate \_Sx object.
309 *
310 * The sleep state package returned from the corresponding \_Sx_ object
311 * must contain at least one integer.
312 *
313 * March 2005:
314 * Added support for a package that contains two integers. This
315 * goes against the ACPI specification which defines this object as a
316 * package with one encoded DWORD integer. However, existing practice
317 * by many BIOS vendors is to return a package with 2 or more integer
318 * elements, at least one per sleep type (A/B).
319 *
320 * January 2013:
321 * Therefore, we must be prepared to accept a package with either a
322 * single integer or multiple integers.
323 *
324 * The single integer DWORD format is as follows:
325 * BYTE 0 - Value for the PM1A SLP_TYP register
326 * BYTE 1 - Value for the PM1B SLP_TYP register
327 * BYTE 2-3 - Reserved
328 *
329 * The dual integer format is as follows:
330 * Integer 0 - Value for the PM1A SLP_TYP register
331 * Integer 1 - Value for the PM1A SLP_TYP register
332 *
333 ******************************************************************************/
334acpi_status
335acpi_get_sleep_type_data(u8 sleep_state, u8 *sleep_type_a, u8 *sleep_type_b)
336{
337 acpi_status status;
338 struct acpi_evaluate_info *info;
339 union acpi_operand_object **elements;
340
341 ACPI_FUNCTION_TRACE(acpi_get_sleep_type_data);
342
343 /* Validate parameters */
344
345 if ((sleep_state > ACPI_S_STATES_MAX) || !sleep_type_a || !sleep_type_b) {
346 return_ACPI_STATUS(AE_BAD_PARAMETER);
347 }
348
349 /* Allocate the evaluation information block */
350
351 info = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_evaluate_info));
352 if (!info) {
353 return_ACPI_STATUS(AE_NO_MEMORY);
354 }
355
356 /*
357 * Evaluate the \_Sx namespace object containing the register values
358 * for this state
359 */
360 info->relative_pathname = acpi_gbl_sleep_state_names[sleep_state];
361
362 status = acpi_ns_evaluate(info);
363 if (ACPI_FAILURE(status)) {
364 if (status == AE_NOT_FOUND) {
365
366 /* The _Sx states are optional, ignore NOT_FOUND */
367
368 goto final_cleanup;
369 }
370
371 goto warning_cleanup;
372 }
373
374 /* Must have a return object */
375
376 if (!info->return_object) {
377 ACPI_ERROR((AE_INFO, "No Sleep State object returned from [%s]",
378 info->relative_pathname));
379 status = AE_AML_NO_RETURN_VALUE;
380 goto warning_cleanup;
381 }
382
383 /* Return object must be of type Package */
384
385 if (info->return_object->common.type != ACPI_TYPE_PACKAGE) {
386 ACPI_ERROR((AE_INFO,
387 "Sleep State return object is not a Package"));
388 status = AE_AML_OPERAND_TYPE;
389 goto return_value_cleanup;
390 }
391
392 /*
393 * Any warnings about the package length or the object types have
394 * already been issued by the predefined name module -- there is no
395 * need to repeat them here.
396 */
397 elements = info->return_object->package.elements;
398 switch (info->return_object->package.count) {
399 case 0:
400
401 status = AE_AML_PACKAGE_LIMIT;
402 break;
403
404 case 1:
405
406 if (elements[0]->common.type != ACPI_TYPE_INTEGER) {
407 status = AE_AML_OPERAND_TYPE;
408 break;
409 }
410
411 /* A valid _Sx_ package with one integer */
412
413 *sleep_type_a = (u8)elements[0]->integer.value;
414 *sleep_type_b = (u8)(elements[0]->integer.value >> 8);
415 break;
416
417 case 2:
418 default:
419
420 if ((elements[0]->common.type != ACPI_TYPE_INTEGER) ||
421 (elements[1]->common.type != ACPI_TYPE_INTEGER)) {
422 status = AE_AML_OPERAND_TYPE;
423 break;
424 }
425
426 /* A valid _Sx_ package with two integers */
427
428 *sleep_type_a = (u8)elements[0]->integer.value;
429 *sleep_type_b = (u8)elements[1]->integer.value;
430 break;
431 }
432
433return_value_cleanup:
434 acpi_ut_remove_reference(object: info->return_object);
435
436warning_cleanup:
437 if (ACPI_FAILURE(status)) {
438 ACPI_EXCEPTION((AE_INFO, status,
439 "While evaluating Sleep State [%s]",
440 info->relative_pathname));
441 }
442
443final_cleanup:
444 ACPI_FREE(info);
445 return_ACPI_STATUS(status);
446}
447
448ACPI_EXPORT_SYMBOL(acpi_get_sleep_type_data)
449